So I've got a plunger style drain in a tub. I can remove the top of the plunger, but in all of the videos i see, unscrewing the top also removes the whole unit. Well, it does not, and I'm left with the screw to remove it from the drain. The screw is stuck, and I cannot get any kind of leverage to get it unscrewed. Does anyone have a method to remove this? I've attached pictures.